Reliability evaluation of the hybrid-redundancy sensor fault tolerate system in the dredging perception system

Abstract

The accurate evaluation of equipment reliability is critical in engineering applications and especially challenging for equipment with complex structures and high reliability requirements. In this paper, a reliability evaluation method based on semi-Markov process is proposed and applied to the hybrid-redundancy sensor fault tolerant (HRSFT) system within the perception system of a cutter suction dredger (CSD). The method takes into account the harsh operating environment of the CSD sensor, and considers the temporal occurrence of sensor faults as well as the imperfection of the sensor fault diagnosis and isolation (SFDI). The outcomes of the model applied to a case study indicate that three key factors, namely, the failure rate of the sensors, the false alarm rate (FAR) of the SFDI system and the self-correction rate (SCR) of the HRSFT system, have a significant impact on the system reliability. Additionally, we performed a comparative analysis between the HRSFT and Double Redundancy Sensor Fault Tolerant (DRSFT) systems, from which the superiority of the HRSFT system in terms of reliability is demonstrated. A series of experiments were conducted with varying parameters values, to show the high adaptability of the model to the HRSFT system.